Background:
CARAlert was established in March 2016 by the Australian Commission on Safety and Quality in Health Care for the Antimicrobial Use and Resistance in Australia (AURA) Surveillance System. CARAlert provides timely communication on critical antimicrobial resistances (CARs) to health departments in each state and territory to inform infection prevention and control strategies.
Methods:
CARAlert uses established laboratory testing and confirmation systems to capture data on CARs – resistances to last line antimicrobials that are uncommon or rare, but with the capacity to become established in Australia. Laboratories that confirm CARs enter results into a national database at the time of confirmation.
Results:
From 1 April 2016 to 23 May 2023, over 10,814 CARs were reported.
Carbapenemase-producing Enterobacterales (CPE) has been the most prevalent CAR reported annually, except in 2017 when azithromycin non-susceptible Neisseria gonorrhoeae (ANSNG) dominated.
CPE reports declined nationally following a peak in 2019. All states/territories except NT had an increase in CPE reports in 2022 compared to 2021. The vast majority of CPE were IMP- and NDM-types. In 2022, IMP-types comprised 54% all CPE reported, and 30% were NDM-types; however, there was considerable regional variation.
Multidrug-resistant Shigella species increased rapidly from 2018. This CAR was ranked second to CPE in 2020; fifth overall in 2021, and fourth in 2022.
Carbapenemase-producing Pseudomonas aeruginosa have been reported in low but increasing numbers. There were seven reports of Enterobacterales with transmissible resistance to colistin (mcr-1.1) and 30 reports of Candida auris.
Conclusions:
Several CARs are detected in Australia on a regular basis. In 2022, higher numbers were reported for most CARs, compared with the previous year; there was notable variation between sates and territories, and evidence of local outbreaks of carbapenemase-producing organisms. The return of international travel after the COVID-19 pandemic has coincided with an increase in reports of ANSNG and MDR Shigella in 2023.